In any M-series family, I’ve always assumed that P and E cores were the same, whether it’s a base or Ultra variant. That isn’t correct, though.
Apple silicon
Low Power mode operates pre-emptive control of CPU core frequency to deliver the best compromise between low power use and performance. Here’s how it does so.
Two important catches that can cause a macOS installation to fail in Apple silicon: using the DFU port, and not setting up ownership correctly. Both are explained here.
Some support USB4, others don’t. Some share the controller, others don’t. Some support DFU mode but then can’t be used to create a bootable external disk on Apple silicon.
Which versions of macOS can you ‘dual boot’, should you install them all on the internal SSD, or is a bootable external disk better, and when would you need to virtualise?
How CPU P cores have a frequency limit applied in Low Power mode, and how macOS regulates power use or temperature by controlling core frequency.
How FileVault and APFS Encrypted are enabled and managed differently, and details of how they work internally. Concentrates on T2 and Apple silicon Macs, but also covers older Intel models.
How Apple silicon CPUs control core frequencies and power use when running in Low Power mode. Includes M4 Pro and M3 Pro data, and estimates of energy requirements.
Apple refers to Energy Modes and Power Modes, and despite older MacBook Pro models offering Low Power mode, tells us that isn’t what Low Power mode is now. Here are the observations and explanations.
It’s September 2016. Apple has just released the iPhone 7, with its first big.LITTLE CPU cores, then 4 days later macOS 10.12 Sierra. How does it transition from there to release the M1 in four years?
The Eclectic Light Company 